Electric guitars and electric basses generally have a long, narrow, wooden neck secured to a wooden body, and are configured with a plurality of strings stretched between a bridge secured to the body surface and a nut secured to the distal end of the neck. Warping referred to as “forward warp” in which the fingerboard side becomes concave, warping referred to as “reverse warp” in which the fingerboard side becomes convex, twisting, and other deformations occur in the neck due to changes in string tension, environmental temperature and humidity, and other factors. Conventionally, a neck reinforcement member is attached to the neck to increase the rigidity of the neck and prevent warping and other deformation of the neck.
In the correction device disclosed in Patent Document 1 (Japanese Laid-open Utility Model Application No. 7-34483), a reinforcement member referred to as an adjusting rod is mounted on the neck, and the tension of the adjusting rod is adjusted to prevent or correct warping of the neck.
In the neck warping prevention structure disclosed in Patent Document 2 (Japanese Laid-open Utility Model Application No. 63-191387), a long, narrow plate-shaped metal reinforcement member is mounted on the neck, whereby neck warping is prevented. In the neck warping prevention structure disclosed in Patent Document 3 (Japanese Laid-open Patent Application No. 2001-13957), a reinforcement member made of sheet metal is embedded in the neck, whereby rigidity and strength are increased and warping and other deformation of the neck are prevented.
In the stringed instrument disclosed in Patent Document 4 (Japanese Laid-open Patent Application No. 02-73295), a cast structural member for reinforcement is embedded in the neck and body, which are molded from a resin, whereby the rigidity and strength of the neck and body are increased; and frets are integrally formed with the cast structural member, whereby the work for attaching the frets is simplified.